SECTION CAST IN PLACE CONCRETE PART 1 GENERAL 1.01 RELATED DOCUMENTS

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1 SECTION CAST IN PLACE CONCRETE PART 1 GENERAL 1.01 RELATED DOCUMENTS A. Drawings and general provisions of the Contract, including General and Supplementary Conditions and Division 1 Specification Sections, apply to this Section SUMMARY A. This Section specifies cast-in-place concrete, including reinforcement, concrete materials, mix design, placement procedures, and finishes. B. Related Sections include the following: 1. Division 2 Section "Earthwork" for drainage fill under slabs-on-grade SUBMITTALS A. General: In addition to the following, comply with submittal requirements in ACI 301. B. Product Data: For each type of manufactured material and product indicated. C. Design Mixes: For each concrete mix QUALITY ASSURANCE A. Installer Qualifications: An experienced installer who has completed concrete work similar in material, design, and extent to that indicated for this Project and whose work has resulted in construction with a record of successful in-service performance. B. Manufacturer Qualifications: A firm experienced in manufacturing ready-mixed concrete products complying with ASTM C 94 requirements for production facilities and equipment. C. Source Limitations: Obtain each type of cement of the same brand from the same manufacturer's plant, each aggregate from one source, and each admixture from the same manufacturer. D. Comply with ACI 301, "Specification for Structural Concrete," including the following, unless modified by the requirements of the Contract Documents. 1. General requirements, including submittals, quality assurance, acceptance of structure, and protection of in-place concrete. 2. Formwork and form accessories. 3. Steel reinforcement and supports. 4. Concrete mixtures. 5. Handling, placing, and constructing concrete. PART 2 PRODUCTS 2.01 FORMWORK A. Furnish formwork and form accessories according to ACI STEEL REINFORCEMENT A. Reinforcing Bars: ASTM A 615/A 615M, Grade 60, deformed. B. Plain-Steel Wire: ASTM A 82, as drawn. C. Plain-Steel Welded Wire Fabric: ASTM A 185, fabricated from as-drawn steel wire into flat sheets. CAST IN PLACE CONCRETE

2 D. Deformed-Steel Welded Wire Fabric: ASTM A 497, flat sheet CONCRETE MATERIALS A. Portland Cement: ASTM C 150, Types I or II or Type I/II. B. Normal-Weight Aggregate: ASTM C 33, uniformly graded, not exceeding 1-1/2-inch nominal size. C. Water: Potable and complying with ASTM C 94. D. Synthetic Fiber: Fibrillated or monofilament polypropylene fibers engineered and designed for use in concrete, complying with ASTM C 1116, Type III, 1/2 to 1-1/2 inches long ADMIXTURES A. General: Admixtures certified by manufacturer to contain not more than 0.1 percent water-soluble chloride ions by mass of cement and to be compatible with other admixtures. Do not use admixtures containing calcium chloride. B. Air-Entraining Admixture: ASTM C RELATED MATERIALS A. Vapor Retarder: Multi-ply reinforced polyethylene sheet, ASTM E 1745, Class C, not less than 7.8 mils thick; or polyethylene sheet, ASTM D 4397, not less than 10 mils thick. B. Fine-Graded Granular Material: Clean mixture of crushed stone, crushed gravel, and manufactured or natural sand; ASTM D 448, Size 10, with 100 percent passing a No. 4 sieve and 10 to 30 percent passing a No. 100 sieve; complying with deleterious substance limits of ASTM C 33 for fine aggregates. C. Joint-Filler Strips: ASTM D 1751, asphalt-saturated cellulosic fiber, or ASTM D 1752, cork or self-expanding cork CURING MATERIALS A. Absorptive Cover: AASHTO M 182, Class 2, burlap cloth made from jute or kenaf, weighing approximately 9 oz./sq. yd. dry. B. Moisture-Retaining Cover: ASTM C 171, polyethylene film or white burlap-polyethylene sheet. C. Water: Potable CONCRETE MIXES A. Comply with ACI 301 requirements for concrete mixtures. B. Prepare design mixes, proportioned according to ACI 301, for normal-weight concrete determined by either laboratory trial mix or field test data bases, as follows: 1. Compressive Strength (28 Days): 3000 psi. 2. Slump: 4 inches. C. Add air-entraining admixture at manufacturer's prescribed rate to result in concrete at point of placement having an air content of 6.0 percent within a tolerance of plus 1.0 or minus 1.5 percent. 1. Air content of trowel-finished interior concrete floors shall not exceed 3.0 percent CONCRETE MIXING A. Ready-Mixed Concrete: Comply with ASTM C 94. CAST IN PLACE CONCRETE

3 PART 3 EXECUTION 3.01 FORMWORK A. Design, construct, erect, shore, brace, and maintain formwork according to ACI VAPOR RETARDER A. Install, protect, and repair vapor-retarder sheets according to ASTM E 1643; place sheets in position with longest dimension parallel with direction of pour. B. Lap joints 6 inches and seal with manufacturer's recommended tape. 1. Cover vapor retarder with fine-graded granular material, moisten, and compact with mechanical equipment to elevation tolerances of plus 0 inch or minus 3/4 inch STEEL REINFORCEMENT A. Comply with CRSI's "Manual of Standard Practice" for fabricating, placing, and supporting reinforcement. 1. Do not cut or puncture vapor retarder. Repair damage and reseal vapor retarder before placing concrete JOINTS A. General: Construct joints true to line with faces perpendicular to surface plane of concrete. B. Construction Joints: Locate and install so as not to impair strength or appearance of concrete, at locations indicated or as approved by Architect. C. Isolation Joints: Install joint-filler strips at junctions with slabs-on-grade and vertical surfaces, such as column pedestals, foundation walls, grade beams, and other locations, as indicated. 1. Extend joint fillers full width and depth of joint, terminating flush with finished concrete surface, unless otherwise indicated. D. Contraction (Control) Joints in Slabs-on-Grade: Form weakened-plane contraction joints, sectioning concrete into areas as indicated. Construct contraction joints for a depth equal to at least one-fourth of the concrete thickness, as follows: 1. Grooved Joints: Form contraction joints after initial floating by grooving and finishing each edge of joint with groover tool to a radius of 1/8 inch. Repeat grooving of contraction joints after applying surface finishes. Eliminate groover marks on concrete surfaces. 2. Sawed Joints: Form contraction joints with power saws equipped with shatterproof abrasive or diamond-rimmed blades. Cut 1/8-inch- wide joints into concrete when cutting action will not tear, abrade, or otherwise damage surface and before concrete develops random contraction cracks CONCRETE PLACEMENT A. Comply with recommendations in ACI 304R for measuring, mixing, transporting, and placing concrete. B. Do not add water to concrete during delivery, at Project site, or during placement. C. Consolidate concrete with mechanical vibrating equipment FINISHING FORMED SURFACES A. Smooth-Formed Finish: As-cast concrete texture imparted by form-facing material, arranged in an orderly and symmetrical manner with a minimum of seams. Repair and patch tie holes and defective areas. Completely remove fins and other projections. CAST IN PLACE CONCRETE

4 1. Apply to concrete surfaces exposed to public view or to be covered with a coating or covering material applied directly to concrete, such as waterproofing, dampproofing, veneer plaster, or painting. 2. Apply the following rubbed finish, defined in ACI 301, to smooth-formed finished concrete. a. Smooth-rubbed finish. B. Related Unformed Surfaces: At tops of walls, horizontal offsets, and similar unformed surfaces adjacent to formed surfaces, strike off smooth and finish with a texture matching adjacent formed surfaces. Continue final surface treatment of formed surfaces uniformly across adjacent unformed surfaces, unless otherwise indicated FINISHING UNFORMED SURFACES A. General: Comply with ACI 302.1R for screeding, restraightening, and finishing operations for concrete surfaces. Do not wet concrete surfaces. B. Screed surfaces with a straightedge and strike off. Begin initial floating using bull floats or darbies to form a uniform and open-textured surface plane before excess moisture or bleedwater appears on the surface. 1. Do not further disturb surfaces before starting finishing operations. C. Scratch Finish: Apply scratch finish to surfaces to receive concrete floor topping, and other bonded cementitious floor finish, unless otherwise indicated. D. Trowel Finish: Apply a hard trowel finish to floor and slab surfaces exposed to view or to be covered with resilient flooring, carpet, ceramic or quarry tile set over a cleavage membrane, paint, or another thin film-finish coating system. E. Trowel and Fine-Broom Finish: Apply a partial trowel finish, stopping after second troweling, to surfaces indicated and to surfaces where ceramic or quarry tile is to be installed by either thickset or thin-set methods. Immediately after second troweling, and when concrete is still plastic, slightly scarify surface with a fine broom. F. Nonslip Broom Finish: Apply a nonslip broom finish to surfaces indicated and to exterior concrete platforms, steps, and ramps. Immediately after float finishing, slightly roughen trafficked surface by brooming with fiber-bristle broom perpendicular to main traffic route TOLERANCES A. Comply with ACI 117, "Specifications for Tolerances for Concrete Construction and Materials." 3.09 CONCRETE PROTECTION AND CURING A. General: Protect freshly placed concrete from premature drying and excessive cold or hot temperatures. Comply with ACI for cold-weather protection, and follow recommendations in ACI 305R for hot-weather protection during curing. B. Evaporation Retarder: Apply evaporation retarder to concrete surfaces if hot, dry, or windy conditions cause moisture loss approaching 0.2 lb/sq. ft. x h before and during finishing operations. Apply according to manufacturer's written instructions after placing, screeding, and bull floating or darbying concrete, but before float finishing. C. Begin curing after finishing concrete, but not before free water has disappeared from concrete surface. D. Curing Methods: Cure formed and unformed concrete for at least seven days by moisture curing, moisture-retaining-cover curing, curing compound, or a combination of these as follows: 1. Moisture Curing: Keep surfaces continuously moist for not less than seven days with the CAST IN PLACE CONCRETE

5 following materials: a. Water. b. Continuous water-fog spray. c. Absorptive cover, water saturated and kept continuously wet. Cover concrete surfaces and edges with 12-inch lap over adjacent absorptive covers. 2. Moisture-Retaining-Cover Curing: Cover concrete surfaces with moisture-retaining cover for curing concrete, placed in widest practicable width, with sides and ends lapped at least 12 inches, and sealed by waterproof tape or adhesive. Immediately repair any holes or tears during curing period using cover material and waterproof tape FIELD QUALITY CONTROL A. Testing Agency: Engage a qualified independent testing and inspecting agency to sample materials, perform tests, and submit test reports during concrete placement according to requirements specified in this Article. Perform tests according to ACI Testing Frequency: Obtain at least one composite sample for each 100 cu. yd. or fraction thereof of each concrete mix placed each day REPAIRS A. Remove and replace concrete that does not comply with requirements in this Section. END OF SECTION CAST IN PLACE CONCRETE